Hey everyone im a new owner of a 1996 Bonneville SE. Just got it friday. I recently had a 97 mustang v6. I got into a accident with it (no injusrie) and wrote it off. :( . I went car shoppin come across this bonneville. I think i made a good choice and i think it will take my mustang. Im impressed on how fast these cars are. I have one question i heard in the 96 models the EGR valve casing melts the plastic intake manifold and coolant enters through the intake. If this is true how can i solve this from ever happening to my car? I will have pics up of my bonne as soon as i get windows tinted (next wednesday).
Thanks

there are some aftermarket solutions out there, but I dont think anyone on here has tried them. The failure usually happens after the car has 100k miles on it, if you watch your coolant level you might be able to spot it early and get it replaced before it causes any major damage.

I caught mine late and hydrolocked my engine, and it was like $1100 to fix. That is probably the worst that can happen.

Well in my opinion the easiest thing you can do is replace the upper intake manifold (or at least take it off and inspect it). I recently replaced my upper intake as proactive maintenance -- I didn't want to deal with any problems down the road. Come to find out the original part was doing OK after 117k, but I put a revised aftermarket intake on there (which has reinforced areas to prevent this type of thing from happening) and I think I'll be fine for the life of the car.

Dorman and Motormite (same company, different brands) both make aftermarket upper intakes for this engine. I believe its about $150 for a replacement. Its a afternoon job if you are handy with tools, otherwise pay a mechanic to do it

Beyond that, the car is really rock solid. Be nice to the transmission and you'll be fine.

Your car may have already had this failure and been fixed. On the top of the upper intake manifold, there'* some casting marks. Can you describe them, or take a pic?

the casts should be little dials with numbers on them, and in the middle is an arrow. We need the numbers or letters that those arrows point to.

im gonna call the dealership today at work and find out all the maitenance thats been done to this car. If it hasnt been fixed im gonna go with and aftermarket intake just to be on the safe side.

Equally as important to replacing the upper intake manifold is to replace the lower intake gaskets. They deteriorate faster than the upper intake manifold!! Mine were really rough after only 77,000 miles!!

look at the ID sticker front left next to the map sensor.
If it is a Rochester product it is the original intake.
If it is Delphi or something else it was replaced and you should be ok.

http://www.bonnevilleclub.com/forum/...pic.php?t=5349
http://www.bonnevilleclub.com/forum/...pic.php?t=8522